<?php
/**
 * Created by PhpStorm.
 * User: Administrator
 * Date: 2017/9/20
 * Time: 11:34
 */
$s = 'banana';
$i = strpos($s,'an');
$i = strpos($s,'an',2);
var_dump($i);
if ($i!==false){
    echo "找到了";
}